Is there any way of avoiding it?
There are surgical techniques that have been proven to minimise the risk. Firstly, a technique called fascial interposition added to the standard procedure is now accepted as the most reliable method of performing vasectomy. In the standard technique, a short piece of the vas deferens is cut and removed, and the remaining two ends are tied. Fascial interposition involves pulling the sheath covering the vas deferens over one severed end, then sewing it shut to create a natural tissue barrier. The aafp site has some photographs and an explanation.
There are surgical techniques that have been proven to minimise the risk. Firstly, a technique called fascial interposition added to the standard procedure is now accepted as the most reliable method of performing vasectomy. In the standard technique, a short piece of the vas deferens is cut and removed, and the remaining two ends are tied. Fascial interposition involves pulling the sheath covering the vas deferens over one severed end, then sewing it shut to create a natural tissue barrier. The aafp site has some photographs and an explanation.
Some of the early studies3,10 report that using fascial interposition, recanalization is reduced to zero. These studies are quite small. A Chinese study6 of 7 techniques involving 2713 men found that vasectomy plus interposition is the most reliable vas occlusion technique. A review of previous studies16 published in 2004 concluded that "Five comparative studies including one high quality randomized clinical trial provided good evidence that fascial interposition increases the occlusive effectiveness of ligation and excision".
Secondly, there is strong evidence that using cautery to seal the ends increases reliability. Combining fascial interposition with cautery provides the highest level of occlusive effectiveness.16
Thirdly, the length of vas segment removed may have a bearing on how reliable vasectomy is. It should be pointed out that using fascial interposition and cautery remain the most important aspects. One study14 found that "Physicians with a high rate of success removed a significantly longer section of vas than physicians exhibiting higher failure rates. At least 15 mm. of vas should be excised to maximize the success of the procedure. Excised vas segments less than 15 mm. had up to a 25-fold greater incidence of failure". Another study13 recommends removal of 3-5 cm.
There is a version of vasectomy called the "Open Ended" technique. Here, the testicular end is not closed. Provided fascial interposition and cautery are used on the other ends, this technique is still as reliable as standard techniques.
